front 1 1) The detector of light during de-etiolation (greening) of a tomato plant is (are) ________. A) carotenoids D) auxin | back 1 C |
front 2 2) Plant hormones ________. B) change their shape in response to stimulus | back 2 D |
front 3 3) Which of the following mechanisms is the correct sequence of
events that takes place during the plant responses to internal and
external signals? C) reception, transduction, and response | back 3 C |
front 4 4) Which of the following mechanisms is in the correct sequence of steps (I-IV as listed below) that takes place during the formation of de-etiolation (greening) response proteins in plants? I. Detection of light signal A) I, III, II, and IV | back 4 B |
front 5 5) Which of the following can function in signal transduction in plants?
A) only I, III, and IV B) only I, II, and V C) only I, III, and V D) only II, III, and V | back 5 C |
front 6 6) Plant hormones produce their effects by ________.
III. modifying the structure of the nuclear envelope membrane A) only I | back 6 D |
front 7 7) Plant hormonal regulation differs from animal hormonal regulation in that ________. A) there are no dedicated hormone-producing organs in plants as there are in animals B) all production of hormones is local in plants with little
long-distance transport D) only animal hormones may have either external or internal receptors | back 7 A |
front 8 8) Auxins in plants are known to affect which of the following processes?
A) only I and II | back 8 B |
front 9 9) Experiments on the positive phototropic response of plants indicate that ________. A) light destroys auxin D) auxin can move to the shady side of the stem | back 9 D |
front 10 10) What are the primary sites of auxin (IAA) production in plants? A) shoot apical meristem and young leaves D) ripening fruits | back 10 A |
front 11 11) What are the primary sites of ethylene production in high concentrations in plants? A) shoot apical meristem and young leaves D) ripening fruits | back 11 D |
front 12 12) Which one of the following hormones regulates cell division in plants? A) auxin (IAA) D) cytokinins | back 12 D |
front 13 13) Which one of the following hormones stimulates stem elongation and pollen tube growth? A) auxin (IAA) D) cytokinins | back 13 C |
front 14 14) Generally, each hormone has multiple functions in plants depending on ________.
A) I, II, III, and IV B) I, II, and III | back 14 B |
front 15 15) Apical dominance in plants is under the control of ________. A)
sugar D) sugar and various plant hormones | back 15 D |
front 16 16) Arrange the following steps that occur during drought tolerance in plants in a correct sequence.
A) I, II, III, and IV | back 16 A |
front 17 17) Which of the following statements best summarizes the acid growth
hypothesis in an actively growing shoot? C) Auxins and gibberellins together act as a lubricant to help stretch cellulose microfibrils. D) Auxins activate aquaporins that increase turgor pressure in the cells. | back 17 B |
front 18 18) Which of the following conclusions is supported by the research
of both Peter Boysen-Jensen and Charles and Francis Darwin on shoot
responses to light? C) Once shoot tips have been cut, normal growth cannot be
induced. | back 18 B |
front 19 19) An eccentric millionaire botanist has offered a $25,000
scholarship to anyone who can successfully get a plant to grow through
a vertical maze in complete darkness. The maze is not in a box; the
maze is simply drawn on the wall, and the contestants must get their
plant to grow in a pattern that matches the path through the maze. You
need the money and feel confident that you can accomplish this task.
Which of the following techniques will help you succeed? | back 19 B |
front 20 20) You have a small tree in your yard that is the height that you
want it, but does not have as many branches as you want. How can you
prune it to trigger it to increase the number of branches? B) Cut off the tips of the main shoots. | back 20 B |
front 21 21) As cytokinins are primarily produced in roots, what route would
they travel to influence lateral shoot formation in a recently topped
tree? C) phloem | back 21 D |
front 22 22) Who might be interested in using cytokinins? B) consumers, to spray on fruit before eating to enhance taste C) florists, to dip stems in to keep leaves green longer | back 22 B |
front 23 23) If a farmer wanted more loosely packed clusters of grapes, he
would most likely spray the immature bunches with ________. C) cytokinins | back 23 B |
front 24 24) ________ prevents seeds from germinating until conditions are
favorable for the growth of the plant. C) Gibberellin | back 24 D |
front 25 25) A population of plants experiences several years of severe drought. Much of the population dies due to lack of water, but a few individuals survive. You set out to discover the physiological basis for their adaptation to such an extreme environmental change. You hypothesize that the survivors have the ability to synthesize higher levels of ________ than their siblings do. A) auxin | back 25 D |
front 26 26) If you were shipping green bananas to a supermarket thousands of
miles away, which of the following chemicals would you want to
eliminate from the plants' environment? C) ethylene | back 26 C |
front 27 27) In the fall, the leaves of some trees change color. This happens
because chlorophyll breaks down and the accessory pigments become
visible. What hormone is responsible for this? C) cytokinin | back 27 D |
front 28 28) Which type of mutant would be most likely to produce a bushier phenotype? A) auxin overproducer D) strigolactone underproducer | back 28 D |
front 29 29) Vines in tropical rain forests must grow toward large trees
before being able to grow toward the sun. To reach a large tree, the
most useful kind of growth movement for a tropical vine presumably
would be ________. B) negative phototropism | back 29 B |
front 30 30) Upon exposure to blue light, plants not only begin to grow toward
the light, but move their chloroplasts to the sunny side of each cell.
The adaptive advantage of moving chloroplasts to the sunny side of
each cell ________. B) increases production of phototropic hormones | back 30 A |
front 31 31) Mammalian eyes sense light because the photoreceptor cells have
molecules called opsins, which change structure when exposed to light.
Which of the following plant molecules would be analogous to mammalian
opsins in their light-sensing ability? B) auxin and Pfr D) cytokinins and phototropins | back 31 C |
front 32 32) Seed packets give a recommended planting depth for the enclosed
seeds. The most likely reason some seeds are to be covered with only
1/4 inch of soil is that the ________. C) seeds require a higher temperature to germinate D) seeds are very sensitive to waterlogging | back 32 B |
front 33 33) Suppose a plant had a photosynthetic pigment that absorbed
far-red wavelengths of light. In which of the following environments
could that plant thrive? C) on the ocean floor, in very deep waters D) on mountaintops, closer to the Sun | back 33 B |
front 34 34) The biological clock controlling circadian rhythms must ultimately ________. A) depend on environmental cues D) speed up or slow down with increasing or decreasing temperature | back 34 B |
front 35 35) Which of the colors of visible light induces curvature in coleoptile most effectively? A) red D) orange | back 35 B |
front 36 36) Phytochrome plays a critical role in seed germination. Which of
the colors maximizes the seed germination? C) violet | back 36 A |
front 37 37) Many plants flower in response to day-length cues. Which of the
following statements best summarizes this phenomenon? C) Long-day plants flower in response to long days, not short
nights. | back 37 D |
front 38 38) Plants often use changes in day length (photoperiod) to trigger
events such as dormancy and flowering. It is logical that plants have
evolved this mechanism because photoperiod changes ________. B) predict moisture availability D) can reset the biological clock | back 38 A |
front 39 39) A gardener in Canada wants to surprise his mother on her birthday
and make her favorite hibiscus bush flower in May instead of at the
end of June. The bush is growing in the greenhouse. Which of the
following might make the hibiscus bush flower early? B) grafting leaves of a hibiscus that was exposed to short nights C)
exposing flower buds of the hibiscus bush to long nights | back 39 B |
front 40 40) Which of the following environmental factors can be sensed by plants? I) gravity II) pathogens III) wind A) only I and III | back 40 D |
front 41 41) Shoots that grow vertically toward the sun can be characterized as ________. A) positive for phototropism and negative for gravitropism D) positive for phototropism and neutral for gravitropism | back 41 A |
front 42 43) The rapid leaf movements resulting from a response to touch
(thigmotropism) primarily involve ________. C) aquaporins | back 42 A |
front 43 44) In extremely cold regions, woody species may survive freezing temperatures by ________. A) emptying water from the vacuoles to prevent freezing D) increasing cytoplasmic levels of specific solute concentrations, such as sugars | back 43 D |
front 44 45) Most scientists agree that global warming is underway; thus, it
is important to know how plants respond to heat stress. Which of the
following would be a useful line of inquiry to try and improve plant
response and survival to heat stress? B) increased production of heat-shock proteins D) protoplast fusion experiments with xerophytic plants | back 44 B |
front 45 46) When an arborist prunes a limb off a valuable tree, he or she may
paint the cut surface. The primary purpose of the paint is to
________. C) stimulate growth of the cork cambium to "heal" the wound D) block entry of pathogens through the wound | back 45 D |
front 46 47) You are out working in your garden, and you notice that one of
your favorite flowering plants has black, dead spots on the leaves.
You immediately suspect that the plant has been invaded by a pathogen
and has initiated a(n) ________. B) hypersensitive response C) resistance response | back 46 B |
front 47 48) Generalized defense responses in organs distant from the infection site are called ________. A) hyperactive responses D) hyperplasia | back 47 B |
front 48 49) A particular species of virus carries a gene for salicylate
hydroxylase, an enzyme that breaks down salicylic acid. Will this
virus be more or less virulent to plants than other viruses? C) same virulent | back 48 A |
front 49 50) Which event during the evolution of land plants favored the
synthesis of secondary compounds? C) the association of the roots of land plants and fungi D) the rise of herbivory | back 49 D |
front 50 51) For a plant to initiate chemical responses to herbivory, before
it is directly affected by herbivores, ________. C) gene-for-gene intraspecific recognition must occur D) phytoalexins must be released | back 50 B |
front 51 52) You may have observed plants rotate towards a light source, thereby increasing the plant's ability to intercept light energy and increase photosynthesis. You, however, are given the task of preventing grass seedlings from rotating toward the light. Using your knowledge of phototropism, which of the following experimental procedures would you use to complete your task? A) Cover the growing tip of the grass seedling with black
paper. C) Cover the portion of the seedling below the tip with a black
shield. | back 51 A |
front 52 53) A plant scientist was hired by a greenhouse operator to devise a
way to force iris plants to bloom in the short days of winter. Iris
normally blooms as a long-day (short-night) plant. Which of the
following has the best chance of creating iris blooms in
winter? B) Increase the temperature to more closely follow summer
temperatures. D) Interrupt the long winter nights with a brief period of light. | back 52 D |
front 53 54) An individual plant was discovered that could not grow towards light. After some research, it was determined that the reason was a defective gene that did not allow for the level of cell elongation necessary for a phototropic response. This mutation greatly reduces the fitness of the individual plant. Which reason best describes the reason for the loss of fitness? A) The plant was too short to attract insects for
pollination. | back 53 B |
front 54 1) The hormone that helps plants respond to drought is A) auxin. D) ethylene. | back 54 B |
front 55 2) Auxin enhances cell elongation in all of these ways except A) increased uptake of solutes. D) cell wall loosening. | back 55 C |
front 56 3) Charles and Francis Darwin discovered that B) red light is most effective in shoot phototropism. C) light destroys auxin. | back 56 D |
front 57 4) How may a plant respond to severe heat stress? D) by increasing the proportion of unsaturated fatty acids in cell membranes, reducing their fluidity | back 57 C |
front 58 5) The signaling molecule for flowering might be released earlier
than usual in a long-day plant exposed to flashes of C) red light followed by far-red light during the night. D) far-red light during the day. | back 58 B |
front 59 6) If a long-day plant has a critical night length of 9 hours, which
24-hour cycle would prevent flowering? C) 4 hours light/8 hours dark/4 hours light/8 hours dark D) 8 hours light/8 hours dark/light flash/8 hours dark | back 59 B |
front 60 7) A plant mutant that shows normal gravitropic bending but does not
store starch in its plastids would require a reevaluation of the role
of ________ in gravitropism. C) statoliths | back 60 C |